This invention relates generally to gliding vehicles, such as rockets, missiles, aircraft, and projectiles, and more particularly to guiding such gliding vehicle.
Atmospheric vehicles that can glide, or that otherwise have significant glide phases, include rockets, missiles, aircrafts, and projectiles. Typically, such vehicles are controllable so that they reach a desired target or destination. They may be controlled by a guidance algorithm. Existing compact closed-form guidance algorithms for gliding flight maximize the range and cross-range while satisfying the aimpoint and final velocity orientation requirements. Compact, closed form algorithms exist to control the time-of-flight of powered vehicles but such algorithms for gliding vehicles have previously been unavailable. To achieve range and cross-range maximization, as well as time-of-flight control for gliding vehicles, open-loop or perturbation feedback algorithms may be utilized. However, such algorithms are expensive to design for a particular application, and are furthermore not robust to airframe and environment variations. For these and other reasons, therefore, there is a need for the present invention.
The invention relates to guiding a gliding vehicle. A method of the invention allows the range of the glide phase of a gliding vehicle to be maximized, while satisfying final flight path angle and aimpoint requirements. The method may also control the time-of-flight of the gliding value to a desired value, while satisfying final flight path angle and aimpoint requirements. The time-of-flight control can correct for winds, off-nominal launch conditions, and rocket motor variations, among other factors. Both time-of-flight control and range and cross-range maximization can be achieved by the inventive method, utilizing a compact closed-loop approach.
The method provides a unified generic structure that is able to accommodate a wide variety of mission profiles. The method is easily implemented in missile flight hardware in particular, and easily optimized by a designer for a particular application. Because the method is closed loop, it is robust as well. Still other aspects, advantages, and embodiments of the invention will become apparent by reading the detailed description that follows, and by referencing the accompanying drawings.